jmorris
01-11-2014, 06:38 PM
The first gun given to me was a Benjamin .22 cal air rifle when I was 11 but it has been dead for years due to worn out parts. After ordering an RWS 34 to play with I came across a rebuild kit from Pyramyd air that cost about $28 including the special tool to take them apart (I was quoted $100 to rebuild it years ago).
Start by removing the stock screw and stock. Then remove the two roll pins that hold the muzzle cap inplace and bring the piston/rod back far enough to line up the pump handle pin with the lower muzzle cap hole and remove that pin. Now you can replace the piston head.
http://i121.photobucket.com/albums/o213/jmorrismetal/reloading/air/IMG_20140111_140148_195_zpsbcb63fb3.jpg
Next remove the trigger/safety (don't loose the detent ball for the safety) and rear retaining cap. The spring and hammer are under a little pressure but not too much, in any case remove these parts.
http://i121.photobucket.com/albums/o213/jmorrismetal/reloading/air/IMG_20140111_140413_347_zpse37f43b2.jpg
They send a tool that is square on one end that allows you to remove the retainer for the valve body.
http://i121.photobucket.com/albums/o213/jmorrismetal/reloading/air/IMG_20140111_141341_021_zpsefa43a2c.jpg
Opposite the square end of the tool, it is threaded to remove the valve guide. This took some "tapping" to get this out of mine.
http://i121.photobucket.com/albums/o213/jmorrismetal/reloading/air/IMG_20140111_141407_713_zpsc2568a57.jpg
The kit comes with all of the seals you need to replace and a new check valve spring but I did reuse the original lead washer instead of the PTFE split washer they provided.
http://i121.photobucket.com/albums/o213/jmorrismetal/reloading/air/IMG_20140111_142635_196_zps7932f7a6.jpg
Be VERY careful reassembling the valve body retainer. If you mess up the threads, both are brass and fine thread, you are going to be SOL. I put the tool in a vise and rotated the tube around while keeping everything in alignment. This too will take a little pressure (I also used air tool oil).
Then reassemble the rest like it came apart. I also cleaned everything once I had it all apart.
Before it wouldn't hold enough air to move a pellet and I have no idea what they are supposed to be but with a 14.3g pellet
3 pumps avg 407 fps
5 pumps avg 507 fps
10 pumps avg 647 fps
5 pumps and let it sit for half an hour went 505.6 with a second 5 pump shot right after going 505.0, so I guess old faithful is back in business.
http://i121.photobucket.com/albums/o213/jmorrismetal/reloading/air/IMG_20140111_155444_277_zpsebb4fa6f.jpg
Start by removing the stock screw and stock. Then remove the two roll pins that hold the muzzle cap inplace and bring the piston/rod back far enough to line up the pump handle pin with the lower muzzle cap hole and remove that pin. Now you can replace the piston head.
http://i121.photobucket.com/albums/o213/jmorrismetal/reloading/air/IMG_20140111_140148_195_zpsbcb63fb3.jpg
Next remove the trigger/safety (don't loose the detent ball for the safety) and rear retaining cap. The spring and hammer are under a little pressure but not too much, in any case remove these parts.
http://i121.photobucket.com/albums/o213/jmorrismetal/reloading/air/IMG_20140111_140413_347_zpse37f43b2.jpg
They send a tool that is square on one end that allows you to remove the retainer for the valve body.
http://i121.photobucket.com/albums/o213/jmorrismetal/reloading/air/IMG_20140111_141341_021_zpsefa43a2c.jpg
Opposite the square end of the tool, it is threaded to remove the valve guide. This took some "tapping" to get this out of mine.
http://i121.photobucket.com/albums/o213/jmorrismetal/reloading/air/IMG_20140111_141407_713_zpsc2568a57.jpg
The kit comes with all of the seals you need to replace and a new check valve spring but I did reuse the original lead washer instead of the PTFE split washer they provided.
http://i121.photobucket.com/albums/o213/jmorrismetal/reloading/air/IMG_20140111_142635_196_zps7932f7a6.jpg
Be VERY careful reassembling the valve body retainer. If you mess up the threads, both are brass and fine thread, you are going to be SOL. I put the tool in a vise and rotated the tube around while keeping everything in alignment. This too will take a little pressure (I also used air tool oil).
Then reassemble the rest like it came apart. I also cleaned everything once I had it all apart.
Before it wouldn't hold enough air to move a pellet and I have no idea what they are supposed to be but with a 14.3g pellet
3 pumps avg 407 fps
5 pumps avg 507 fps
10 pumps avg 647 fps
5 pumps and let it sit for half an hour went 505.6 with a second 5 pump shot right after going 505.0, so I guess old faithful is back in business.
http://i121.photobucket.com/albums/o213/jmorrismetal/reloading/air/IMG_20140111_155444_277_zpsebb4fa6f.jpg